As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
In some applications, multiple information handling systems may be used simultaneously. For example, data centers may include multiple web servers, mail servers, general purpose servers, storage servers and similar devices mounted in vertical racks. These information handling systems may be managed by information technology (IT) personal in a many to one relationship such that a single IT person may manage the multiple information handling systems. Typically, the IT person uses a Keyboard, Video and Mouse (KVM) switch to connect multiple servers to a single mouse, keyboard and video monitor in a point-to-point topology.
The point-to-point topology, however, requires three (3) cables (e.g., one cable for each of the mouse, video and monitor functions) to connect each of the information handling systems to the KVM switch. In a rack including, for example, forty (40) servers, there may be as many as one-hundred twenty (120) cables used to connect the information handling systems to the KVM switch. Since many data centers include large numbers of information handling systems, cable management is quickly becoming a large problem. Additionally, most KVM switches may only support a maximum of eight (8) information handling systems. In a rack including more than eight (8) information handling systems, the appropriate number of additional KVM switches must be added to the data center. The KVM switches additionally may occupy one slot in the rack, thus reducing the number of information handling systems that may be included in the rack.
One solution to reducing the number of cables used to connect multiple information handling systems to a KVM switch is to use a master switch card coupled to multiple slave cards. The master switch card may be located in the first information handling system in the rack (e.g., the information handling system located in the top slot of the rack). The master card is then coupled to a slave card in the next information handling system in the rack by a single cable. The remaining information handling systems include slave cards that are connected by daisy chaining the systems together. In this solution, the master card is directly connected to a management system being used to monitor the data center. This direct connection is undesirable because the operation of the entire system is dependent upon the master card. If the master card fails or the information handling system containing the master card loses power, the management system cannot receive any information from any of the information handling systems in the rack.
In another solution, each information handling system may include a local management card that converts each of information handling system's signals into encoded and packetized signals carried over a cable. This solution eliminates the problem of relying on a master card to control the entire system but increases the cost of the system because complex circuitry is required to generate the packetized signals.